This little trick is one we've talked about before on the blog and the podcast. I'm pleased to finally be able to offer you some audio examples of it in use. There are lots of techniques for using multiple mics on a guitar cabinet but most of them involve using a close mic and another mic anywhere from a few feet away to across the room. The goal in these cases is to include the room sound.
What's done a lot less often is using two close mics. I stumbled on this trick the day I got my first Sennheiser e609s. I threw them out on stage along with some SM 57s and planned to A/B them on each guitarist as the night went on and just pick the one that sounded best for each player. Five seconds into the first sound check I found that I had a fat mic and a skinny mic and I could create guitar Nirvana just by balancing the two channels against each other. I never looked back.
The principle in effect here is phase cancellation caused by the difference in position of the two mics and the slightly different frequency responses. It causes comb filtering and you control how much by changing the gain on each mic. It makes mic positioning a lot less important which is a nice advantage on a festival stage. if you get an inexperienced opener with screechy tone, you just push up the fat mic and ride the skinny mic down. With more experienced players it lets you react to the tonal changes they create. You can make the fat tones a little fatter or mellow out the solos to get them to fit perfectly in the mix.
Another advantage is that in a dense mix, you can make a solo cut through without making it louder. I find that I generally ride with the fat mic a little higher than the skinny mic. When a solo comes up I just swap the positions of the faders and the notes stand up in the mix without taking anyone's head off.
So there you have it Brethren of the Knob and Fader. With the addition of a second mic to your guitar inputs you open up a world of possibilities. Advanced users can even try micing the back of a cab. You'll find anything from additional corpulent fatness on a Fender open back combo, to bone crushing bass notes coming off the back of a Marshall half stack. Use with caution though, it can get ugly and out of control in a hurry.
- SNR Mini Podcast - Double Guitar Mic Trick - Anthony Kosobucki demonstrates our favorite live and studio trick for getting great guitar sounds.